Traction apparatus and rope take-up mechanism of traction apparatus

Abstract

A traction apparatus which impresses a desired traction force to a body to be pulled is provided. The traction apparatus includes: a traction mechanism that includes a harness coupled to the body to be pulled, a rope having one end attached to the harness, and a take-up drum attaching to an other end of the rope and impressing the traction force on the body to be pulled by taking up the rope; a first pulley that engages at a predetermined wrapping angle the rope to which the traction force is impressed by being taken up by the take-up drum, a rope load being impressed to the first pulley from the rope; a coupling plate that rotatably holds the first pulley, the rope load being impressed to the coupling plate from the first pulley; a load sensor plate that holds the coupling plate at one end portion thereof, the rope load being impressed to the load sensor from the coupling plate; an outer frame that fixes an other end portion of the load sensor plate; and a load cell adhered to a surface of the load sensor plate.

The invention claimed is: 
     
       1. A traction apparatus that impresses a desired traction force to a body to be pulled, the traction apparatus comprising:
 a traction mechanism that includes a harness coupled to the body to be pulled, a rope having a first end attached to the harness, and a take-up drum attached to a second end of the rope and impressing the traction force on the body to be pulled by taking up the rope; 
 a first pulley that engages, at a predetermined wrapping angle, the rope to which the traction force is impressed by being taken up by the take-up drum, a rope load being impressed to the first pulley from the rope; 
 a coupling plate that rotatably holds the first pulley, the rope load being impressed to the coupling plate from the rope via the first pulley; 
 a load sensor plate that holds the coupling plate at a first end portion thereof, the rope load being impressed to the load sensor plate from the rope via the first pulley and the coupling plate; 
 an outer frame that fixes a second end portion of the load sensor plate; 
 a load cell adhered to a surface of the load sensor plate, the load cell detecting an amount of strain of the load sensor plate caused by the rope load; and 
 a rotation mechanism that rotates the outer frame in agreement with a take-up position of the rope on a take-up surface of the take-up drum, 
 the first pulley rotating in accordance with rotation of the outer frame. 
 
     
     
       2. The traction apparatus according to  claim 1 , comprising a second pulley that engages the rope closer to the harness than the first pulley. 
     
     
       3. The traction apparatus according to  claim 2 , wherein a lengthwise direction of the load sensor plate is a direction that forms equal angles with each of a first movement path of the rope from the second pulley to the first pulley and a second movement path of the rope from the first pulley to the take-up drum. 
     
     
       4. The traction apparatus according to  claim 3 , wherein the rope engages the first pulley so that the first movement path and the second movement path are orthogonal. 
     
     
       5. The traction apparatus according to  claim 1 , comprising a load sensor mechanism that includes the first pulley, the coupling plate, and the load sensor plate, wherein the load sensor mechanism is configured to be rotatable in compliance with a rope take-up position of the take-up drum. 
     
     
       6. The traction apparatus according to  claim 5 , comprising a second pulley that engages the rope closer to the harness than the first pulley, the second pulley is configured to be rotatable in compliance with movement of a first movement path of the rope from the first pulley to the second pulley accompanying rotation of the load sensor. 
     
     
       7. The traction apparatus according to  claim 1 , wherein the rope load is a tensile load. 
     
     
       8. A rope take-up mechanism of a traction apparatus impressing a desired traction force on a body to be pulled by a harness coupled to the body to be pulled and a rope having a first end of the rope attached to the harness, the rope take-up mechanism comprising:
 a take-up drum that attaches to a second end of the rope and that impresses the traction force on the body to be pulled by taking up the rope; 
 a first pulley that engages, at a predetermined wrapping angle, the rope to which the traction force is impressed by being taken up by the take-up drum, and on which a rope load is impressed from the rope; 
 a second pulley that engages the rope closer to the harness than the first pulley; 
 a load sensor mechanism that includes: a coupling plate rotatably holding the first pulley, the rope load being impressed to the coupling plate from the rope via the first pulley; a load sensor plate holding the coupling plate at a first end portion thereof, the rope load being impressed to the load sensor plate from the rope via the first pulley and the coupling plate; an outer frame fixing a second end portion of the load sensor plate; and a load cell adhered to a surface of the load sensor plate, the load cell detecting an amount of strain of the load sensor plate caused by the rope load; and 
 a rotation mechanism that rotates the outer frame in agreement with a take-up position of the rope on a take-up surface of the take-up drum, 
 the first pulley rotating in accordance with rotation of the outer frame. 
 
     
     
       9. The rope take-up mechanism of the traction apparatus according to  claim 8 , wherein a lengthwise direction of the load sensor plate is a direction that forms equal angles with each of a first movement path of the rope from the second pulley to the first pulley and a second movement path of the rope from the first pulley to the take-up drum. 
     
     
       10. The rope take-up mechanism of the traction apparatus according to  claim 9 , wherein the rope engages the first pulley so that the first movement path and the second movement path are orthogonal. 
     
     
       11. The rope take-up mechanism of the traction apparatus according to  claim 8 , wherein the rope load is a tensile load. 
     
     
       12. The rope take-up mechanism of the traction apparatus according to  claim 8 , wherein the load sensor mechanism is configured to be rotatable in compliance with a rope take-up position of the take-up drum, and
 the second pulley is configured to be rotatable in compliance with movement of a first movement path of the rope from the first pulley to the second pulley accompanying rotation of the load sensor.